I could think of a way to at least save 98 of the prisoners. The first prisoner should open 50 drawers with the numbers 1 to 50. With luck, this guy finds his own number. If not, we have a single prisoner gone.

Before he entered the room, I told him to take all the notes he gathered from the drawers, and put them back into a single one, drawer number one.

I'll tell the next prisoner to check drawer 1. There is a chance he will find his number in there. If not, he can still open another 49 drawers. There is a chance he won't survive this test either. Luckely, I told him to leave drawer number 100 alone and put the 49 gathered notes in drawer 1.

I'll tell the next prisoner to check drawer 1 and 100 and get the contents of drawer 100 in in the first one.

I'll tell the next 97 prisoners to check drawer 1, which will surely contain their numbers.